Property and Equipment (Property and Equipment) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 281.9us-gaap_PropertyPlantAndEquipmentGross	$ 292.8us-gaap_PropertyPlantAndEquipmentGross
Long-term notes receivable	967.7us-gaap_PropertyPlantAndEquipmentNet	1,012.8us-gaap_PropertyPlantAndEquipmentNet
Other property and equipment
Property, Plant and Equipment [Line Items]
Accumulated depreciation	(238.8)	(207.3)
Long-term notes receivable	346.0	387.7
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	41.2	43.0
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	206.0	206.3
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	35.4	36.2
Transportation equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5.1	5.0
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 15.2	$ 11.7

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Subparagraph a

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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